If you're still sad-faced about never getting a go in Concorde we have yet more bad news—air travel is getting slower again. This time we're warping back to 1930s flight speeds, thanks to a new wave of cargo blimps.

The modern freight blimp can sustain a top speed of around 78mph, and according to some reports would be able to carry twice as much cargo as a Boeing 747—while producing 90% less greenhouse emissions.

Professor Sir David King, the UK government's former chief scientific adviser, says he thinks big, helium-powered blimps similar to the Lockheed Martin High Altitude Airship (pictured) are the eco-friendly future of air transport—and will begin to takeover the Taiwan-to-US electronics distribution routes by the end of the decade. [The Guardian]